Diesel fuel oils



Patentea Dec. 30, 1941 J Herschel G. Smith, Wallingford, Troy L. Cantrell,

' Lansdowne, and'Mai-k L. Hill, Yeadon, Pm, as-

signors to Gulf Oil Corporation, Pittsburgh, Pa.,

a corporation of Pennsylvania No Drawing. Application July 12, 1946, 7 Serial No. 683,156 i 4 Claims. (01. 44-68) This invention relates to improved Diesel fueloils and more particularly to Diesel fuel oils which contain small amounts of addition agents which improve the performance characteristics of Diesel engines that burn said improved Diesel fuel oils. V

Diesel engines are generally operated with fuel oils that have a boiling range above that of gasoline and below that of a motor lubricant. They may for instance have initial boiling points of about 400 F. and end boiling points of about 700 F. In the operation of Diesel engines with such petroleum fuel oils various difliculties arise. Often. varnish or gum is formed on the piston surfaces, cylinder walls, valves, and atomizing apparatus of Diesel engines operating on such fuel oils, and the piston rings become stuck. Gum formation on the close fitting pintle valve of the fuel injection equipment results in a rapid drop in power and fluctuating combustion pressure due to inconsistent fuel injection. After several days of operation on ordinary Dieselfuel oils power output. and engine efiiciency decrease and there is a noticeable amount of knocking when the speed of the engine is increased. The engine must frequently be overhauled, cleaned and adjusted to restoreits operating efficiency. Diesel fuel oils used in operating marine Diesel engines often become contaminated with water. As little as 0.1 per cent of Water in a Diesel fuel oil can cause corrosion of fuel injectors so serious that the injectors must necessarily be replaced. With certain straight-run light Pennsylvania type fuel oils the wear on the injectors and plungers is sufficient to render them inaccurate after a few days operation thereby causing erratic engine performance. 'Small and medium size Diesel engines which usually operate on rather light fuel oils in particular operate with lessened efficiency because of insufficient lubrication and corrosion of parts. Corrosion, wear and gum formation on the high a pressure injection pumps, interior cylinder surfaces and piston rings appear to be the major causes for the lessened efficiency with which Diesel engines perform when they are operated on ordinary Diesel fuel oils.

. It is an object of this invention, to provide fuel oils for Diesel engines which will improve the power output and performance characteristics of such engines. A further object is to produce saturated Diesel fuel oils which will deposit very little varnish or gum on the engine parts. A still further object is to provide Diesel fuel oils which will not corrode engine parts if said oils become contaminated with water. Another object is to provide Diesel fuel oils which will tend to lessen the wear Other objects will appear on the engine parts. hereinafter.

These objects are accomplished in accordance with the present invention by making improved Diesel fuel oils which contain a small proportion of an aliphatic amine soap made from a long chain primary aliphatic amine that has at least 10 carbon atoms and a long chain aliphatic monocarboxylic acid that has at least 10 carbon atoms and which also contain a small proportion of a polyvalent metal salt of an N-alkenyl, N-alkylol phthalamidic acid, said aliphatic amine soap and polyvalent metal salt being present in suflicient quantities to improve the performance characteristics of Diesel engines burning said Diesel fuel oils.

The aliphatic amine soaps used in our improved Diesel fuel oils are made from primary aliphatic amines having at least 10 carbon atoms and straight chain aliphatic monocarboxy-lic acids that have at least 10 carbon atoms. The normal straight chainprimary aliphatic amines used in preparing. the amine soaps used in the present invention preferably contain from 10 to 20 carbon atoms. Usually normal straight chain, primary alkyl amines such as decyl amine, undecyl amine, dodecyl amine, tetradecyl amine, cetyl amine, octadecyl amine and eicosyl amine are employed, but it is also permissible to use unstraight chain primary aliphatic amines such asundecenyl amine and 9,10-octadecenyl amine (also called oleyl amine). tures of the straight chain primary alkyl amines, such as cocoa-mine, are often used because of their relative cheapness. Cocoamine is a commercial mixture of higher alkyl amines prepared from coconut oil fatty acids. It contains a major amount of primary dodecyl amine, and typical samples thereof have been found to have average molecular weight ranging from 200' to 210.

The aliphatic amine soaps used in our improved Diesel fuel oils are made by reacting amines such as those mentioned in the preceding paragraph MiX- aliphatic monocarboxylic acids containing at least 10 carbon atoms such as capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, ricinolelc acid, linoleic acid and arachidic acid. Technical mixtures of these acids such as may be obtained by hydrolyzing fats or oils such as castor oil, tallow, lard, olive oil, cottonseel oil, linseed oil, palm oil, coconut oil, peanut oil, palm kernel oil, rape oil, etc., may be utilized in preparing the amine soaps employed in the Diesel fuel oils of this invention.

One of the amine soaps which has been found to be avery desirable addition agent to Diesel fuel oils is the cocoamine salt of lauric acid. Cocoamine laurate is prepared by neutralizing 200 parts by weight of lauric acid with 200 parts by weight of cocoarnine which has an average molecular weight of 200.

The Diesel fuels of the present invention also contain a small proportion of a polyvalent metal salt of a N-alkenyl. N-alkylol phthalamidic acid which has the following general formula:

n-i i-a' I wherein n: denotes the numeral 2 or 3, R stands for an alkenyl group, R. represents an alkylol group, and M stands for a divalent or trivalent metal. These divalent and trivalent metal salts of N-alkenyl, N-alkylol phthalamidic acids are prepared by reacting equimolecular quantities of N-alkenyl, N-alkylol amines and phthalic anhydride to form N -alkenyl, N -alky1ol phthalamidic acids, followed by conversion of said acids to the desired divalent or trivalent metal salts thereof. Preferably the alkenyl group contains a long chain of 8 or more carbon atoms and may be an octenyl, decenyl, undecenyl, dodecenyl, tetradecenyl, hexadecenyl, 9,10 octadecenyl, eicosenyl, or other similar long chain group. M preferably stands for calcium, but it may also denote other divalent metals such as magnesium, strontium, barium, zinc, cadmium, lead, tin, copper, nickel or cobalt, or trivalent metals such as aluminum or bismuth. The alkylol group preferably contains from 2 to 4 carbon atoms.

The alkenyl and alkylol groups in the polyvalent metal salts of N -alkenyl, N-alkylol phthalamidic acids are generally introduced therein by making these disubstituted phthalamidic acids from N-alkenyl, N-alkylol amines and phthalic anhydride. These N-alkenyl, N-alkylol amines may in turn conveniently be prepared by reacting equimolecular proportions of 1,2-alkylene oxides with primary alkenyl amines, such as octenyl amine, decenyl amine, 'undecenyl amine, dodecenyl amine, tetradecenyl amine, hexadecenyl amine, 9,10-octadecenyl amine, eicosenyl amine, etc. Among the 1,2-alkylene oxides which may be employed in preparing these N-alkenyl, N-alkylol amines there may be mentioned ethylene oxide, l,2-propylene oxide and 1,2-butylene oxide. The N-alkenyl. N-alkylol amines prepared by the reaction of equimolecular quantities of these 1,2-alkylene oxides with primary alkenyl amines have the following general formula:

11 n R-N(E-(IJ-X wherein It represents an alkenyl group and x stands for hydrogen or a methyl or ethyl group.

In order to exemplify this method of preparing these N-alkenyl, N-alkylol amines we will here describe the preparation of N-9,l0-octadecenyl, N-2-hydroxy-propy1 amine from equimolecular proportions of N-9,10-octadecenyl amine and 1,2- propylene oxide. Into a suitable reaction vessel equipped with a reflux condenser and means for heating and agitating the contents of said Vessel were placed267 parts by weight of 9,10-octadecenyl amine (also called oleyl amine). Then 58 parts by weight of propylene oxide were gradually added to the reaction mixture while stirring. After the reactants were intimately mixed, the mixture was allowed to stand over night. Then the reaction mixture was refluxed for five hours to complete the reaction. The N-9,l0-octadecenyl, N-2-hydroxypropyl amine thus obtained has the following structural formula:

One of the most readily prepared polyvalent metal salts used in the Diesel fuels of the present invention is the calcium salt of N-9-l0-octadecenyl, N-Z-hydroxy-propyl phthalamidic acid. This compound is prepared by reacting equimolecular quantities of phthalic anhydride and N-9,10-octadecenyl, N-Z-hydroxy-propyl amine to form N-9,10-octadecenyl, N-2-hydroxy-propyl phthalamidic acid, which is then converted to its calcium salt by neutralization with calcium hydroxide. A more detailed description of the preparation of this compound is given in the following paragraph.

Into a suitable reaction vessel were placed 325 parts by weight of N-9,10-octadecenyl, N-z-hydroxy-propyl amine and 148 parts by weight of phthalic anhydride. This mixture was agitated and heated to from 180 to 220 F. While maintaining the temperature and continuing the asitation, 37 parts by weight ofcalcium hydroxide were added. and the reaction mixture was held at this temperature a period of 10 hours. The reaction product thus obtained was the calcium salt of N-9,10-octadecenyl, N-2-hydroxy-propyl phthalamidic acid.

Suitable Diesel fuel oils of the present invention may be made by adding to an ordinary Diesel fuel oil as little as 0.0004 per cent by weight of one of the aliphatic amine soaps mentioned hereinabove and 0.0004 per cent by weight of one of the polyvalent metal salts of N-alkenyl, N-allavlol phthalamidic acids, which are hereinbefore described. In adding these compounds to a Diesel fuel oil we find it convenient to blend 92 parts by weight of a Texas oil having a viscosity of 300 S. U. V. at F. with 4 parts by weight of an aliphatic amine soap made from a long chain primary aliphatic amine that has at least 10 carbon atoms and a long chain aliphatic monocarboxylic acid that has at least 10 carbon atoms and with 4 parts by weight of a polyvalent metal salt of N-alkenyl, N-alkylol phthalamidic acid. We denote this blend of a Texas oil with an allphatic amine soap and a polyvalent metal salt of an N-alkenyl, N-alkylol phthalamidic acid as a concentrate of Diesel fuel addition agents; We add from 0.01 per cent to l per cent by volume of this concentrate of Diesel fuel addition agents to a Diesel fuel oil in preparing the improved Diesel fuel oils comprehended by the present invention. It is therefore obvious that the improved Diesel fuel oils of the present invention contain from about 0.0004 per cent to about 0.04 per cent by weight of one of the aliphatic amine soaps hereinbefore described and from about 0.0004 per cent to about 0.04 per cent by weight of one of the polyvalentmetal salts hereinbefore described. If desired, we may dispense with the Texas oil of 300 S. U. V. at 100 F. and add the aliphatic amine soap and the polyvalent metal salt directly to the Diesel oil in the desired proportions. We generally find it practical to add 0.5 per cent by volume of the concentrate of Diesel fuel addition agents to an ordinary Diesel fuel oil which means that the Diesel fuel oils of the present invention generally'contain about 0.02 per cent by weight of one of the aliphatic amine soaps described hereinbefore and about 0.02 per cent by weight of one of the polyvalent metal salts described hereinabove.

A preferred concentrate of Diesel fuel addition agents which has been used in preparing some .of the improved Diesel fuel oils of the present invention is prepared by blending 4 per cent by weight of the cocoamine salt of lauric acid and I 4 per cent by weight of the calcium salt of N-9, lo-octadecenyl, N-Z-hydroxypropyl phthalamidic acid with 92 per cent by weight of a Texas oil having a viscosity of 300 S. U. V. at 100 F. This concentrate of Diesel fuel addition agents has the following properties:

Gravity, A. P. I 22.1 Viscosity, S. U. V.

Flash, 0C, "F v Fire, 00, F 400 Pour: F 10 Table I With Concentrate Without Concentrate Gravity, A. P. I Viscosity. S. U. V.:

Pour, F

Sulfur, Per C nt Water and Sediment. Per Cent Segimtent, A. S. T. M. D473-38T, Per

Carbon Residue, Per Cent...

Precipitation N bright Corrosion Test:

A. S. T. M. D665-44T- Steel Strip, Appearance Area Rusted. Per Cent....

rust

bright nil 100 The following table gives the comparative properties of a light Diesel fuel oil and an improved light Diesel fuel oil of the present invention which was made therefrom by blending 0.5 per cent by volume of the concentrate of Diesel fuel addition agents described above with 99.5 per cent by volume of the light Diesel fuel oil.

- Table II- With Con- Without contrate Concentrate Gravity, A. P. I 42. 9 43.0 Viscosity, S. U. V.: 100 F 35. 4 35.2 Flash, P-M; A. S. T..M. 093-42, F.'. 164 164 Pour, F-.. 5 5 Color, Saybolt +20 +18 Sulfur, L, Per Cent 0. 08 0.06 Water anzl Sediment, Per Cent nil nil Carbon Resi'lue, Per Cent 0.01 0.01 Carbon Residue on 10% Bottoms, Per

Cent 0.04 0.04 Precipitation No nil nil Copper Strip Test, 212 3 hrs good good Neutralization No 0. 0i 0. 01 Acid Heat, F.: A. S. 'I. M. 0481-30. 6 5 Unsaturation, Per Cent: Method 550.2, 'Gov't 3 3 An ne Point,v F. A S T M.

D6ll-44T 170.0 171.0 Cetane No 'iethod 62 02 Diesel Inriex No. 74 74 Ash, Per Cent nil nil Distillation, Gas Oil:

A. S. T. M. 13158-41- Over Point, F 380 380 En'i Point, F 638 10% at, F- 440 441 a at, 496 494 at, F 549 545 Corrosion 'lest No. l of Patent No.

2,371,853 bright rust Corrosion Test:

Steel Stri Appearance bright rust Area usted, Per Cent nil fuel oils. The close fitting pintle valves in the injection equipment of Diesel engines burning our improved fuel oils do not become covered with gum or corroded, and therefore the combustion pressure and power output remain constant even after over 1000 hours of operation. This is an important advantage especially in connection with the operation of marine Diesel engines such as those used in power barges. Our new Diesel fuel oils substantially prevent corrosion and wear of the high pressure injection pumps, interior cylinder surfaces and piston rings, and reduce the tendency for piston rings to stick. Our Diesel fuels thus improve markedly the p rformance of Diesel engines, particularly those of small and medium size that usually operate on rather light fuel oils. The Diesel oils of the present invention decrease the tendency toward ring sticking and varnish formation on cylinder walls,

valves and atomizing apparatus, thereby improving engine performance, power output and engine efi'iciency. The speed of Diesel engines burning our improved fuel oils may be increased with less knocking, and such engines will operate for a longer running time without having to be overhauled. If our Diesel fuel oils become contaminated with a little water, no serious corrosion of the injectors will ensue, since the addition agents added to our fuel oils increase their water tolerance. The wear on the plungers and injectors decreases considerably when our fuel oils are employed. Our improved Diesel fuel oils successfully counteract many of the factors that decrease the efliciency of Diesel engines operating on ordinary Diesel fuels.

Resort may be had to such modifications and variations as fall within the spirit of the invention and the scope of the appended claims.

What we claim is:

1. An improved Diesel fuel oil which contains a small proportion of an aliphatic amine soap made from a long chain primary aliphatic amine 7 that has at least 10 carbon atoms and a long chain aliphatic monocarboxylic acid that has at least 10 carbon atoms and which alsocontains a small proportion of a salt selected from the group consisting otdivalent and trivalent, ,metal salts of an N-allrenyl, N-alkylol phthalamidic acid,

said aliphatic amine soap and polyvalent metal salt being present in sumcient quantities to. retard corrosion, wear, gum formation and ring sticking in a Diesel engine burning said Diesel fuel oil.

2. An improved Diesel fuel oil which contains a small proportional an aliphatic amine soap made from a long chain primary aliphatic amine that has at least 10 carbon atoms and a 1on8 chain aliphatic monocarboxylic acid that has at least 10 carbon atoms and which also contains a small proportion 01' a divalent metal salt of an N-alkenyl, N-alkylol phthalamidic acid. said allphatic amine soap and divalent metal salt being present in suflicient quantities to retard corrosion,

- wear, gum formation and ring sticking in a Diesel by weight of an aliphatic amine soap made from a long chain primary aliphatic aminethat has at least -l0 carbon atoms and a long chain aliphatic monocarboxylic acid that has at least 10 carbon atoms and-which also contains from about 0.0004 per cent to about 0.04 per cent by weight of a divalent metal salt of an N-alkenyl, N-alkyiol phthalamidic acid wherein said alkenyl group contains at least 8 carbon atoms and said alkylol group contains from 2 to 4 carbon atoms.

4. An improved Diesel fuel oil which contains about 0.02 per cent by weight oi cocoamine laurate and about 0.02 per cent by weight of the calcium salt of N-9,10-octadecenyl, N-2-hydroxy-propyi phthalamidic acid.

HERSCHEDG. SMITH. TROY L. CANTRELL. MARK L. HILL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Name Date Anderson Mar. 14, 1944 Wasson June 11, 1946 Smith et al. Sept. 24, 1946 Number 

